检索结果-内蒙古大学图书馆

Numerical methods for the design of gradient-index optical coatings

APPLIED OPTICS 2012年第34期51卷 8277-8295页

作者： Anzengruber, Stephan W. Klann, Esther Ramlau, Ronny Tonova, Diana Carl Zeiss Jena GmbH D-73447 Oberkochen Germany Michigan State Univ Dept Math E Lansing MI 48824 USA Johannes Kepler Univ Linz Inst Ind Math A-4040 Linz Austria

We formulate the problem of designing gradient-index optical coatings as the task of solving a system of operator equations. We use iterative numerical procedures known from the theory of inverse problems to solve it with respect to the coating refractive index profile and thickness. The mathematical derivations necessary for the application of the procedures are presented, and different numerical methods (Landweber, Newton, and Gauss-Newton methods, Tikhonov minimization with surrogate functionals) are implemented. Procedures for the transformation of the gradient coating designs into quasi-gradient ones (i.e., multilayer stacks of homogeneous layers with different refractive indices) are also developed. The design algorithms work with physically available coating materials that could be produced with the modern coating technologies. (C) 2012 Optical Society of America

关键词： refractive index profile Optical coatings design algorithm Numerical methods Inverse method gradient coating

来源：评论

学校读者我要写书评

暂无评论

Optimizing the design for a two-phase cooling loop heat pipe Part A: Numerical model, validation and application to a case study

引用

APPLIED THERMAL ENGINEERING 2016年 99卷 892-904页

作者： Esarte, J. Bernardini, A. Blanco, J. M. Sancibrian, R. Fdn CETEAN CEMITEC Aditech Tajonar 20 Pamplona 31006 Spain Univ Pais Vasco EHU Escuela Tecn Super Ingn Bilbao Dept Ingn Nucl & Mecan Fluidos Alameda Urquijo S-N Bilbao 48013 Spain Univ Cantabria Escuela Tecn Super Ingn Dept Ingn Estruct & Mecan Avda Castros S-N E-39005 Santander Spain

High-power light-emitting diodes can dissipate several times more heat power than conventional lighting devices, while keeping the junction temperature below a security value, in order to assure reliability and low light decay. No fans are usually permitted, so the heat dissipation solution should adopt new technological advances that are required in the form of lighter, shape-embedded heat-sink devices. The present study addresses the implementation of a special heat-dissipation technology, known as a loop heat pipe, consisting of an evaporator, a condenser, a compensation chamber, and vapor and liquid lines for cooling particular types of devices, such as light-emitting diodes, through the phase-change cooling method. In this paper a new algorithm to simulate this loop heat pipe is presented. This mathematical model is based on steady-state energy balance equations for each main component. Finally, a validation procedure through a fully monitored experimental test is performed to show the effects of different key parameters on the heat load such as radius and length of the vapor line, wick thickness and condensing temperature. It produces an effective optimization of the original design, representing an innovative tool for design assessment, to determine the influence of these key performance parameters for each particular application. Finally, a case study is presented for the optimization of a loop heat pipe design, applied to the cooling of an 80 W street lamp. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： Analytical solution design algorithm Junction temperature LED cooling Loop heat pipe optimization Model validation

来源：评论

学校读者我要写书评

暂无评论

design of scalar functional observers of order less than (ν-1)

引用

INTERNATIONAL JOURNAL OF CONTROL 2006年第12期79卷 1654-1659页

作者： Trinh, H. Tran, T. D. Nahavandi, S. Deakin Univ Sch Informat Technol & Engn Geelong Vic 3217 Australia

This paper presents a new method of designing scalar functional observers of order less than the well-known upper bound ( v-1). A condition for the existence of observers of order p where 1 <= p <= (v-1) is given. A simple and effective algorithm for solving the constrained generalized Sylvester equation is proposed. Several numerical examples are given to illustrate the attractiveness of the design algorithm.

关键词： Scalar efficient algorithm Observers design algorithm FUNCTIONALS new methods Sylvester

来源：评论

学校读者我要写书评

暂无评论

design overstrength of steel eccentrically braced frames

引用

INTERNATIONAL JOURNAL OF STEEL STRUCTURES 2013年第3期13卷 529-545页

作者： Kusyilmaz, Ahmet Topkaya, Cem Middle E Tech Univ Dept Civil Engn TR-06531 Ankara Turkey

The paper reports an analytical study on the design overstrength of steel eccentrically braced frames (EBFs). The study aimed at examining the influence of geometrical factors and seismic hazard on the design overstrength of EBFs. Pursuant to this goal a computer program which facilitates EBF designs was developed. The algorithm of the program adopts the lightest uniform frame design and library of link-beam-brace sub-assemblages concepts. The design output from the program was compared with published solutions and the results indicate that the algorithm developed as a part of this study is capable of providing lighter framing solutions. A parametric study was conducted using the developed computer program. The results indicate that the frames considered in this study have on average higher overstrength values when compared with the codified value even without considering potential increases due to material overstrength and strain hardening. The design overstrength was found to be influenced primarily by the link length to bay width ratio and the bay width, and secondarily by the building height and seismic hazard level.

关键词： structural steel eccentrically braced frame overstrength design algorithm

来源：评论

学校读者我要写书评

暂无评论

A comprehensive model for determining technological innovation level in supply chains using green investment, eco-friendly design and customer collaborations factors

引用

RAIRO-OPERATIONS RESEARCH 2022年第4期56卷 2775-2800页

作者： Beigizadeh, Razieh Delgoshaei, Aidin Ariffin, Mohd Khairol Anuar Hanjani, Sepehr Esmaeili Ali, Ahad Islamic Azad Univ Dept Management Rasht Branch Rasht 41335 Guilan Iran Univ Putra Malaysia Dept Mech & Mfg Engn Serdang 43400 Selangor Malaysia Islamic Azad Univ Dept Management North Tehran Branch Tehran 14515 Iran Lawrence Technol Univ Dept Ind Engn Southfield MI 48075 USA

Technological innovations play a crucial role in designing an effective green supply chain. However, it is crucial to know the factors influencing technological innovation in a green supply chain. Some preconceptions show that technological innovation in a business can be affected by internal and external factors, and therefore there must be correlations between such factors to flourish the technological innovation and, subsequently, the green supply chain. Besides, predicting the technological innovation level in a supply chain can be vital and direct it to the Industry 5.0 goals. In this research, a 3-phased framework will be proposed to predict the Technological Innovation Level of Green Supply Chains. The scope of this research includes Green Investment, Eco-friendly design and Customer Collaborations. In the 1st phase of the framework, dependent and independent factors considering the scope of the Research will be determined;and then, using statistical data analysis, the weight of factors, which reflects their impact on technological innovation (dependent factor), will be determined. Then, in the 2nd phase, a comprehensive model will be developed and trained. Using the data of supply chains that were gathered in the first phase, the train and test data would be selected. In continuation, the model will be trained and its performance will be evaluated using some metrics. Then, in the last phase (phase 3), the developed model will be used to predict the technological level of supply chains. The outcomes of this research can help top managers of supply chains to predict the level of technological innovation by investing a certain budget in improving the dependent variables. The outcomes demonstrated that Customer Collaboration (0.481), Eco-friendly design (0.419) and Green Investment (0.41) have significant impacts on technological innovation improvement in the studied cases, respectively. Besides, the results showed the superiority of the K-nearest Neighbor algor

关键词： Green supply chain technological innovation design algorithm green investment eco-friendly design customer collaborations

来源：评论

学校读者我要写书评

暂无评论

Observer design and detection for nonlinear descriptor systems

引用

INTERNATIONAL JOURNAL OF CONTROL 1997年第2期67卷 153-168页

作者： Shields, DN Maths Division Coventry University Coventry CV1 5FB Priory Street United Kingdom

A nonlinear observer is considered for a class of continuous nonlinear descriptor systems subject to unknown inputs and faults. This class is partly characterized by globally Lipschitz nonlinearities, and a member system may be singular and possibly non-causal. The observer structure chosen makes it useful for both state estimation for feedback controls and residual generation for fault detection. Results on the existence of solutions are given and some useful bounds are derived which are important in the observer design, which is based on a transformed system and on the solution of a Riccati equation. The existence, convergence properties and robustness of the observer are investigated by the use of a quadratic Lyapunov function. Conditions are given for a bound to hold on the norm of the transfer function relating the residual error to the disturbance (linear case). A design algorithm is given and applied to the estimation of the states of a flexible joint robot.

关键词： DYNAMIC-SYSTEMS TRANSFER FUNCTIONS Residuals design algorithm Riccati equations Flexible connections Singular Bound Dynamic systems State estimation nonlinearity Descriptors

来源：评论

学校读者我要写书评

暂无评论

New design for unconventional timing silent chain system of inline engine

引用

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING 2024年第5期238卷 1154-1169页

作者： An, Lichi Cheng, Yabing Li, Jiabao Zhou, Haigang Jilin Univ Sch Mech & Aerosp Engn Changchun Peoples R China Jilin Univ Sch Mech & Aerosp Engn Remin St 5988 Changchun 130022 Peoples R China

More and more unconventional timing silent chain systems are used in the low-emission vehicles or hybrid vehicles, but engineering practices show that the classical design method cannot ensure the stability and the feasibility anymore. According to the angular velocity fluctuations of crankshaft, the maximum accumulation length is calculated to design the ideal path of the tension side chain. The tension rate is defined to determine the ideal chain path at the loose side. In order to match the ideal chain paths with the actual chain length, the pitch variation algorithm is proposed. Based on a specific inline engine, the unconventional timing silent chain system is designed by the classical design method and the new design method respectively. The design process proves that the new method is belonging to a real parametric design, and it can expediently and quickly obtain the results. With the dynamics simulation comparison, the results show that the operation performance of the unconventional timing system can be roundly and significantly improved by using the new design method. Furtherly, this new design method is not only suitable for the unconventional timing system, but also suitable for the other types of timing systems.

关键词： Timing system silent chain tension rate pitch variation design algorithm

来源：评论

学校读者我要写书评

暂无评论

Automated optimal design of double-layer latticed domes using particle swarm optimization

引用

STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION 2014年第2期50卷 221-235页

作者： Babaei, M. Sheidaii, M. R. Urmia Univ Dept Civil Engn Fac Engn Orumiyeh Iran

Most of the conventional design methods of large-scale domes need deep engineering insight;furthermore, they hardly give the most economical solutions. Therefore, in this paper, a new practical design algorithm is presented to automate optimal geometry and sizing design of the latticed space domes through the idea of using parametric mathematical functions. Moreover, a simple approach is developed for the optimal sizing design of trusses with outsized number of elements. The robust technique of particle swarm optimization is employed to find the solution of the propounded optimization problem. Some numerical examples on the minimum weight design of several famous domes are provided to demonstrate the efficiency of the proposed design algorithm.

关键词： Space structure Latticed dome Truss Automated design Sizing/geometry optimization design algorithm Particle swarm optimization Minimum weight

来源：评论

学校读者我要写书评

暂无评论

Elementary Implementation of a Parameter-Based Generative design System Considering the User Environment

引用

JOURNAL OF ASIAN ARCHITECTURE AND BUILDING ENGINEERING 2014年第2期13卷 333-340页

作者： Ji, Seung Yeul Jun, Han Jong Hanyang Univ Dept Architecture Seoul 133791 South Korea

A generative design system subdivides a real physical space a user actually lives in and recreates it through object-oriented programming, and depending on the situation of the design process, variable data are arranged in a hierarchy to set up parameters so that an efficient shape can be drawn. A pleasant environment of the user space is considered under various space-related conditions during the design process using data obtained from an environment analysis simulation based on the building code. This study focuses on the methodology of processing and utilizing variable data derived by the parameterization of the analysis data through a simulation using sensor measurement equipment to analyze user behavioral design patterns and obtain the intensity of illumination of the interior space, which is the spatial variable data element that forms the actual physical space. After systematizing the variable values through motion capture, during the process of designing, as a sketch, a design algorithm will be formed, which will be utilized as the generative design algorithm. Further, a method for improving the design quality using a computer-based design algorithm will be investigated, and whether the design method can be improved further will be predicted. Relevance to design Practice - This study utilizes various sensor-based IT technologies and environmental analysis data to design an optimal solution fit for a user environment and investigates whether a methodology could be applied to the design process to help improve the design through a generative design system by the processing of variable data.

关键词： generative design system parameter design algorithm freeform furniture design Natural User Interface (NUI)

来源：评论

学校读者我要写书评

暂无评论

Functional Observer design using Linear Matrix Inequalities

引用

OPTOELECTRONICS INSTRUMENTATION AND DATA PROCESSING 2016年第4期52卷 334-340页

作者： Volkov, V. G. Dem'yanov, D. N. Kazan Fed Univ Ul Kremlevskaya 18 Kazan 420008 Russia

It is shown that the problem of observer design for estimating a set of linear combinations of state variables of a plant can be formulated in terms of linear matrix inequalities. An algorithm for constructing functional observers is proposed based on a nonsingular transformation of a plant model in the state space by matrix canonization with subsequent solution of the system of linear matrix inequalities.

关键词： estimation functional observer design algorithm linear matrix inequalities matrix canonization

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：